Let's get this math done. We have 3402 and 4458 and we're going to add them all together.

Step 1: We'll start by adding the digits 2 & 8 in column 1 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 0 & 5 in column 2 and get 6.

Step 3: We'll start by adding the digits 4 & 4 in column 3 and get 8.

Step 4: We'll start by adding the digits 3 & 4 in column 4 and get 7.

So, 3402 + 4458 = 7860.

